Power supply method and power supply circuit of a display device

Abstract

The application provides a power supply method and a power supply circuit of a display device, which are applied to a power supply architecture, the power supply architecture further comprising a power supply battery and a display device, the display device comprising an OLED screen, the power supply circuit comprising a buck-boost converter, the power supply battery being connected with the power supply circuit, and the power supply circuit being connected with the display device, so as to reduce the probability of water ripples. The power supply battery is used to transmit an input voltage to the buck-boost converter; the buck-boost converter is used to switch a current mode to a first mode or a second mode according to the size relationship between the input voltage and a voltage threshold, so as to output a target power supply voltage; and the OLED screen in the display device is powered by the target power supply voltage; wherein the switching time length from switching the current mode from the first mode to the second mode and then from the second mode to the first mode is higher than a time length threshold, and the time length threshold is determined based on the refresh rate of the display device.

Description

Technical Field

[0001] This application relates to the field of power supply technology, and in particular to a power supply method and power supply circuit for a display device. Background Technology

[0002] Organic light-emitting diode (OLED) screens require multiple different supply voltages to function properly. Typically, a driver IC is needed to power the OLED screen by outputting multiple port voltages based on the input battery voltage. This output voltage includes a constant positive voltage, ELVDD (4.6V), used to provide positive voltage to the LEDs in the screen module. Battery voltages generally range from 3.4V to 4.5V; currently, a boost converter can be used to obtain the 4.6V ELVDD voltage.

[0003] However, the above method may produce voltage ripples, which can cause water ripples on the screen and result in a poor user experience. Summary of the Invention

[0004] This application provides a power supply method and power supply circuit for a display device, which reduces the probability of water ripples appearing.

[0005] In a first aspect, a power supply circuit for a display device is provided, applied to a power supply architecture, the power supply architecture further including a power supply battery and a display device, the display device including an OLED screen, the power supply circuit including a buck-boost converter, the power supply battery being connected to the power supply circuit, and the power supply circuit being connected to the display device, wherein: the power supply battery is used to transmit an input voltage to the buck-boost converter; the buck-boost converter is used to switch a current mode to a first mode or a second mode according to the relationship between the input voltage and a voltage threshold, so as to output a target power supply voltage; and to supply power to the OLED screen in the display device through the target power supply voltage; wherein the switching time between switching the current mode from the first mode to the second mode and then switching the current mode back to the first mode is higher than a time duration threshold, the time duration threshold being determined based on the refresh rate of the display device.

[0006] Secondly, a power supply method for a display device is provided, applied to a power supply circuit of the display device in a power supply architecture, the power supply architecture further including a power supply battery and a display device, the display device including an OLED screen, the method comprising: acquiring an input voltage; switching a current mode to a first mode or a second mode according to the magnitude relationship between the input voltage and a voltage threshold, so as to output a target power supply voltage; supplying power through the OLED screen in the target power supply voltage; wherein, the switching time between switching the current mode from the first mode to the second mode and then switching the current mode back to the first mode is higher than a time duration threshold, the time duration threshold being determined based on the refresh rate of the display device.

[0007] In this application, the power supply circuit of the display device can switch the current mode to a first mode or a second mode via a buck-boost converter based on the relationship between the input voltage from the power supply battery and a voltage threshold, so as to output a target power supply voltage; and power the OLED screen in the display device through the target power supply voltage. Specifically, the switching time between switching the current mode from the first mode to the second mode and then back to the first mode is longer than a time threshold, which is determined based on the refresh rate of the display device. In other words, this application reduces the frequency of mode switching, thereby reducing the frequency of output voltage and thus reducing the probability of water ripples appearing. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of a power supply architecture provided in an embodiment of this application;

[0009] Figure 2 This is a schematic diagram of a power supply circuit provided in an embodiment of this application;

[0010] Figure 3 This is a schematic diagram of a power supply circuit for a display device provided in an embodiment of this application;

[0011] Figure 4 This is a schematic diagram of another power supply architecture provided in an embodiment of this application;

[0012] Figure 5 This is a schematic flowchart illustrating a power supply method for a display device provided in an embodiment of this application;

[0013] Figure 6 This is a flowchart illustrating a first specific example of a power supply method for a display device provided in an embodiment of this application;

[0014] Figure 7 This is a flowchart illustrating a second specific example of the power supply method for a display device provided in the embodiments of this application;

[0015] Figure 8This is a schematic diagram of a display device provided in an embodiment of this application. Detailed Implementation

[0016] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the power supply architecture 100 provided in an embodiment of this application. Figure 1 As shown, the power supply circuit 100 includes a power supply battery 101, a power supply circuit 102 (also referred to as a power management integrated circuit (PMIC)), and a display device 103. The power supply battery 101 is connected to the power supply circuit 102, which is connected to the display device 103. The display device 103 includes an organic light-emitting diode (OLED) screen. The power supply circuit 102 can obtain an input voltage from the power supply battery 101 and output a target supply voltage to the display device 103 to power the OLED screen. It should be understood that the OLED screen requires multiple different supply voltages to operate normally. The output voltage includes a constant positive voltage ELVDD (4.6V) (i.e., the target supply voltage). The voltage of the power supply battery typically varies from 3.4V to 4.5V, and the power supply circuit can output a 4.6V ELVDD voltage.

[0018] However, the above method may produce voltage ripples, which can cause water ripples on the screen and result in a poor user experience.

[0019] Figure 2 A schematic diagram of a power supply circuit 200 is shown. (For example...) Figure 2 As shown, the power supply circuit 200 may include a boost converter 201. The boost converter 201 includes an inductor 2011, a first MOSFET 2012, and a second MOSFET 2013.

[0020] For example, when the input voltage of the power supply battery exceeds 4.5V, the first MOSFET 2012 and the second MOSFET 2013 can conduct complementaryly, allowing the boost converter 201 to operate in synchronous mode and output the target supply voltage, i.e., the 4.6V ELVDD voltage, to power the OLED screen in the aforementioned display device. However, when the power supply battery is slow charging, the superimposed battery load fluctuations can cause the input voltage of the boost converter to exceed 4.5V. To stabilize the ELVDD output voltage to 4.6V, the conduction time of the second MOSFET 2013 in the boost converter 201 is too short. When the conduction time limit of the second MOSFET 2013 is reached, the first MOSFET 2012 will operate in low dropout regulator (LDO) mode. It should be understood that in this LDO mode, the first MOSFET 2012 is not fully turned on, and a certain voltage drop will occur on this transistor, which can extend the conduction time of the second MOSFET 2013. However, during the aforementioned mode switching process, the ELVDD voltage exhibits significant voltage ripple. Specifically, when the input voltage changes from below 4.5V to above 4.5V, the boost converter 201 immediately switches from synchronous mode to LDO mode; conversely, when the input voltage changes from above 4.5V to below 4.5V, the boost converter 201 immediately switches back from LDO mode to the aforementioned synchronous mode. In other words, frequent fluctuations in the input voltage around 4.5V will cause ripples of a certain frequency in the ELVDD voltage, resulting in a water ripple effect on the screen.

[0021] In view of this, embodiments of this application provide a power supply method and power supply circuit for a display device. The power supply circuit of the display device can switch the current mode to a first mode or a second mode based on the relationship between the input voltage from the power supply battery and a voltage threshold using a buck-boost converter, so as to output a target power supply voltage; and supply power to the OLED screen in the display device through the target power supply voltage. Specifically, the switching time between switching the current mode from the first mode to the second mode and then switching the current mode back to the first mode is higher than a time duration threshold, which is determined based on the refresh rate of the display device. In other words, this application reduces the frequency of mode switching, thereby reducing the frequency of output voltage and thus reducing the probability of water ripples appearing.

[0022] It should be understood that the display devices involved in the embodiments of this application may be mobile phones, tablets, laptops, handheld computers, mobile internet devices (MIDs), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, smart screens, artificial intelligence (AI) speakers, headphones, terminals in industrial control, terminals in self-driving, terminals in remote medical surgery, terminals in smart grids, terminals in transportation safety, terminals in smart cities, terminals in smart homes, personal digital assistants (PDAs), etc., and the embodiments of this application are not limited to these.

[0023] To facilitate understanding of the embodiments of this application, a more comprehensive description of the embodiments of this application will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the embodiments of this application. However, the embodiments of this application can be implemented in many different forms and are not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the embodiments of this application more thorough and complete. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments of this application belong. The terminology used herein in the description of the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0024] In the description of the embodiments of this application, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the method or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0025] It is understood that the terms "first," "second," etc., used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first MOSFET may be referred to as a second MOSFET, and similarly, a second MOSFET may be referred to as a first MOSFET. Both the first MOSFET and the second MOSFET are MOSFETs, but they are not the same MOSFET. Furthermore, the term "connection" in the specification and claims of this application refers to an electrical connection.

[0026] It should be noted that, in this application, the words "exemplarily" or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplarily" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of words such as "exemplarily" or "for example" is intended to present the relevant concepts in a specific manner.

[0027] Furthermore, "at least one" refers to one or more, while "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, and c can mean: a, or b, or c, or a and b, or a and c, or b and c, or a, b, and c, where a, b, and c can be single or multiple.

[0028] To make the objectives and technical solutions of this application clearer and more intuitive, the power supply method and power supply circuit of the display device provided in the embodiments of this application will be described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0029] Figure 3 A schematic diagram of the power supply circuit 300 for the display device provided in this application is shown below. Figure 3 As shown, the power supply circuit 300 of the display device may include a buck-boost converter 301. The buck-boost converter 301 may be composed of a first MOSFET 3011, a second MOSFET 3012, a third MOSFET 3013, a fourth MOSFET 3014, and an inductor 3015. Figure 3As shown, the first MOSFET 3011 can be connected in series with the second MOSFET 3012 to form a first series branch, and the third MOSFET 3013 and the fourth MOSFET 3014 can be connected in series to form a second series branch. The second series branch and the first series branch are connected in parallel and are connected through the inductor 3015.

[0030] It should be understood that the power supply circuit of the aforementioned display device can be in two different modes, such as a first mode and a second mode. Specifically, the power supply circuit of the display device can select and switch to the corresponding mode based on different input voltages, so as to output the target power supply voltage in that corresponding mode.

[0031] For example, the power supply circuit of the display device can switch the current mode to the first mode when the input voltage is less than the voltage threshold, so as to maintain the output target power supply voltage; or, the power supply circuit of the display device can switch the current mode to the second mode when the input voltage is greater than or less than the voltage threshold, so as to maintain the output target power supply voltage.

[0032] Figure 4 This is a schematic diagram of the power supply architecture 400 provided in this application. Figure 4 As shown, the power supply architecture 400 includes a power supply battery 401, a power supply circuit 402 for the display device, and a display device 403. The display device 403 includes an OLED screen 4031. The power supply circuit 402 for the display device includes a buck-boost converter 4021 composed of a first MOSFET 40211 (also denoted as Q140211), a second MOSFET 40212 (also denoted as Q240212), a third MOSFET 40213 (also denoted as Q340213), a fourth MOSFET 40214 (also denoted as Q440214), and an inductor 40215 (also denoted as L40215). The connection relationships between these multiple circuit components can be found above. Figure 3 The description will not be repeated here to avoid repetition, including:

[0033] The aforementioned power supply battery 401 is used to transmit the input voltage V to the buck-boost converter 4021 in the power supply circuit 402 of the aforementioned display device. in .

[0034] The aforementioned buck-boost converter 4021 is used to adjust the input voltage V according to the aforementioned input voltage V. in With voltage threshold V th Based on the magnitude relationship, the current mode is switched to the first or second mode to output the target supply voltage V. out ; and, through the target power supply voltage V outPower is supplied to the OLED screen 4031 in the aforementioned display device 403.

[0035] For example, the buck-boost converter 4021 described above can determine the input voltage V in From a voltage threshold V less than the above-mentioned th The change is greater than the aforementioned voltage threshold V. th In this case, the current mode is switched to the second mode. In other words, the buck-boost converter 4021 can switch to the second mode after determining the above input voltage V. in From low to high, crossing the aforementioned voltage threshold V th In this case, the current mode will be switched from the first mode to the second mode.

[0036] It should be understood that the first mode described above can only be used to maintain the target output supply voltage when the input voltage is less than the voltage threshold; the second mode described above is used to maintain the target output supply voltage when the input voltage is greater than or less than the voltage threshold. In other words, when the buck-boost converter 4021 determines the input voltage V... in From a voltage threshold V less than the above-mentioned th The change is greater than the aforementioned voltage threshold V. th In this case, before switching the current mode to the second mode, to ensure that the input voltage V in Less than the voltage threshold V th The target supply voltage V can be maintained at the same time. out To achieve efficient power supply to the OLED screen in display device 403, the current mode can be the first mode.

[0037] For example, the buck-boost converter 4021 described above can also determine the input voltage V. in From a voltage threshold greater than the above-mentioned V th The change is less than the aforementioned voltage threshold V. th In this case, the current mode will be switched to the first mode mentioned above. That is, the buck-boost converter 4021 can switch to the first mode mentioned above when the input voltage V is determined. in Crossing voltage threshold V from high to low th In this case, the current mode will be switched from the second mode to the first mode mentioned above.

[0038] It should be understood that the first mode described above can only be used to maintain the target output supply voltage when the input voltage is less than the voltage threshold; the second mode described above is used to maintain the target output supply voltage when the input voltage is greater than or less than the voltage threshold. The input voltage V is determined by the buck-boost converter 4021. in From a voltage threshold greater than the above-mentioned V th The change is less than the aforementioned voltage threshold V. thIn this case, before switching the current mode to the first mode, to ensure that the input voltage V in Greater than the voltage threshold V th The target supply voltage V can be maintained at the same time. out To enable power supply to the OLED screen in display device 403, the current mode can be a second mode.

[0039] In one possible implementation, the buck-boost converter 4021 can keep the first MOSFET 40211 in a normally on state, while the third MOSFET 40213 and the fourth MOSFET 40214 are alternately turned on to switch the current mode to the first mode and output the target supply voltage in the first mode.

[0040] For example, the buck-boost converter 4021 can turn on the third MOSFET 40213 for a period of time and then replace it with the fourth MOSFET 40214 to achieve alternating conduction between the third MOSFET 40213 and the fourth MOSFET 40214.

[0041] For example, the buck-boost converter 4021 can also turn on the fourth MOSFET 40214 for a period of time and then replace it with the third MOSFET 40213 to achieve alternating conduction between the third MOSFET 40213 and the fourth MOSFET 40214. This application does not limit this.

[0042] For example, the buck-boost converter 4021 can also have the second MOSFET 40212 replace the first MOSFET 40211 in the normally on state, that is, the second MOSFET 40212 is in the normally on state, the first MOSFET 40211 is in the normally off state, and the third MOSFET 40213 and the fourth MOSFET 40214 are alternately turned on to switch the current mode to the first mode, and realize the output of the target power supply voltage in the first mode. This application does not limit this.

[0043] In another possible implementation, the buck-boost converter 4021 can also alternately turn on the first MOSFET 40211 and the second MOSFET 40212, and alternately turn on the third MOSFET 40213 and the fourth MOSFET 40214, so as to switch the current mode to the second mode and realize the output of the target supply voltage in the second mode.

[0044] For example, the buck-boost converter 4021 can turn on the first MOSFET 40211 for a period of time, then replace it with the second MOSFET 40212, and cyclically turn it on in this order to achieve alternating conduction between the first MOSFET 40211 and the second MOSFET 40212. Alternatively, the third MOSFET 40213 can be turned on for a period of time, then replace it with the fourth MOSFET 40214, and cyclically turn it on in this order to achieve alternating conduction between the third MOSFET 40213 and the fourth MOSFET 40214. The first MOSFET 40211 can be turned on synchronously with the third MOSFET 40213, and the second MOSFET 40212 can be turned on synchronously with the fourth MOSFET 40214; this application does not limit this.

[0045] For example, the buck-boost converter 4021 can also turn on the first MOSFET 40211 for a period of time, then replace it with the second MOSFET 40212, and cyclically turn it on in this order to achieve alternating conduction between the first MOSFET 40211 and the second MOSFET 40212. Alternatively, the fourth MOSFET 40214 can be turned on for a period of time, then replace it with the third MOSFET 40213, and cyclically turn it on in this order to achieve alternating conduction between the third MOSFET 40213 and the fourth MOSFET 40214. The first MOSFET 40211 can be turned on synchronously with the fourth MOSFET 40214, and the second MOSFET 40212 can be turned on synchronously with the third MOSFET 40213; this application does not limit this.

[0046] For example, the buck-boost converter 4021 can also turn on the second MOSFET 40212 for a period of time, then replace it with the first MOSFET 40211, and cyclically turn it on in this order to achieve alternating conduction between the first MOSFET 40211 and the second MOSFET 40212. Alternatively, the fourth MOSFET 40214 can be turned on for a period of time, then replace it with the third MOSFET 40213, and cyclically turn it on in this order to achieve alternating conduction between the third MOSFET 40213 and the fourth MOSFET 40214. The first MOSFET 40211 can be turned on synchronously with the third MOSFET 40213, and the second MOSFET 40212 can be turned on synchronously with the fourth MOSFET 40214; this application does not limit this.

[0047] For example, the buck-boost converter 4021 can also turn on the second MOSFET 40212 for a period of time, then replace it with the first MOSFET 40211, and cyclically turn it on in this order to achieve alternating conduction between the first MOSFET 40211 and the second MOSFET 40212. Alternatively, the third MOSFET 40213 can be turned on for a period of time, then replace it with the fourth MOSFET 40214, and cyclically turn it on in this order to achieve alternating conduction between the third MOSFET 40213 and the fourth MOSFET 40214. The first MOSFET 40211 can be turned on synchronously with the fourth MOSFET 40214, and the second MOSFET 40212 can be turned on synchronously with the third MOSFET 40213; this application does not limit this.

[0048] It should be understood that after the buck-boost converter 4021 switches the current mode from the first mode to the second mode, the switching time for switching the current mode back from the second mode to the first mode is longer than a time threshold, which can be determined based on the refresh rate of the display device.

[0049] It should also be understood that the power supply circuit of the display device shown above is merely exemplary, and this application does not limit it.

[0050] For example, the first MOSFET 40211 can also be connected in series with the third MOSFET 40213 to form a first series branch, and the second MOSFET 40212 and the fourth MOSFET 40214 can be connected in series to form a second series branch. The second series branch and the first series branch are connected in parallel and are connected through the inductor 40215. Alternatively, the first MOSFET 40211 can also be connected in series with the fourth MOSFET 40214 to form a first series branch, and the second MOSFET 40212 and the third MOSFET 40213 can be connected in series to form a second series branch. The second series branch and the first series branch are connected in parallel and are connected through the inductor 40215. This application does not limit this approach.

[0051] Figure 5 This is a schematic diagram of a power supply method 500 for a display device provided in this application. This method 500 can be applied to the power supply circuit of a display device in a charging architecture, as described above. Figure 3 , Figure 4 The power supply circuit of the display device is shown in the image. For example... Figure 5 As shown, the method 500 includes the following steps:

[0052] S501, the power supply circuit of the display device obtains input voltage from the power supply battery through a buck-boost converter.

[0053] S502, the power supply circuit of the display device switches the current mode to the first mode or the second mode according to the relationship between the input voltage and the voltage threshold through the buck-boost converter, so as to output the target power supply voltage.

[0054] It should be understood that the first mode described above can only be used to maintain the target output supply voltage when the input voltage is less than the voltage threshold; the second mode described above is used to maintain the target output supply voltage when the input voltage is greater than or less than the voltage threshold.

[0055] For example, this voltage threshold can also be called the switching point voltage, and can be expressed as V. th The value can be 4.5V. The above input voltage can be expressed as V. in The target supply voltage output above can be expressed as V. out The power supply circuit of the display device can determine the above input voltage V through a buck-boost converter. in From a voltage threshold greater than the above-mentioned V th The change is less than the aforementioned voltage threshold V. th In this case, switch the current mode to the first mode described above. Alternatively, after determining the input voltage V... in From a voltage threshold V less than the above-mentioned th The change is greater than the aforementioned voltage threshold V. th In this case, switch the current mode to the second mode.

[0056] It should be understood that the switching time between switching the current mode from the first mode to the second mode and then switching the current mode back to the first mode exceeds a time threshold. This time threshold can be determined based on the refresh rate of the display device to avoid frequent mode switching that could lead to high voltage fluctuations in the output, thereby increasing the probability of water ripples appearing.

[0057] S503, the power supply circuit of the display device supplies power to the OLED screen in the display device based on the target power supply voltage through a buck-boost converter.

[0058] It should be understood that OLED screens require multiple different supply voltages to operate properly. Among these different supply voltages is the target supply voltage V output by this application. out That is, a constant positive voltage ELVDD with a value of 4.6V.

[0059] In this application, the power supply circuit of the display device can switch the current mode to a first mode or a second mode via a buck-boost converter based on the relationship between the input voltage from the power supply battery and a voltage threshold, so as to output a target power supply voltage; and power the OLED screen in the display device through the target power supply voltage. Specifically, the switching time between switching the current mode from the first mode to the second mode and then back to the first mode is longer than a time threshold, which is determined based on the refresh rate of the display device. In other words, this application reduces the frequency of mode switching, thereby reducing the frequency of output voltage and thus reducing the probability of water ripples appearing.

[0060] Figure 6 This is a schematic diagram of a power supply method 600 for a display device provided in this application. This method 600 can be applied to the power supply circuit of a display device in a charging architecture. Figure 6 As shown, the method 600 includes the following steps:

[0061] S601, the power supply circuit of the display device obtains input voltage from the power supply battery through a buck-boost converter.

[0062] S602, the power supply circuit of the display device determines the relationship between the input voltage and the voltage threshold through a buck-boost converter.

[0063] For example, this voltage threshold can also be called the switching point voltage, and can be expressed as V. th The value can be 4.6V. The above input voltage can be expressed as V. in The power supply circuit of the display device can compare the above input voltage with the voltage threshold through a buck-boost converter to determine their magnitude relationship.

[0064] S603, when it is determined that the input voltage changes from greater than the voltage threshold to less than the voltage threshold, the power supply circuit of the display device obtains the time interval between the last time the current mode was switched from the first mode to the second mode and then from the second mode to the first mode through the buck-boost converter.

[0065] It should be understood that the first mode described above can only be used to maintain the target output supply voltage when the input voltage is less than the voltage threshold; the second mode described above is used to maintain the target output supply voltage when the input voltage is greater than or less than the voltage threshold. When determining the input voltage V... in From a voltage threshold greater than the above-mentioned V th The change is less than the aforementioned voltage threshold V. th In the case of obtaining the aforementioned time interval, it can be determined that before S603, in order to ensure that the input voltage V in Greater than the voltage threshold V thThe target supply voltage V can be maintained at the same time. out To enable power supply to the OLED screen in the display device, the current mode can be a second mode.

[0066] S604, the power supply circuit of the display device determines the relationship between the interval duration and the aforementioned duration threshold through a buck-boost converter.

[0067] It should be understood that this time threshold is determined based on the refresh rate of the display device, such as the refresh rate of the OLED screen mentioned above.

[0068] S605, when the time interval is greater than the time threshold, the power supply circuit of the display device switches the current mode from the second mode to the first mode through the buck-boost converter to output the target power supply voltage.

[0069] It should be understood that, under the aforementioned input voltage V in Less than the above voltage threshold V th In this case, both of the above modes can output the target supply voltage V. out This is to enable power supply to the OLED screen in the display device. However, to achieve higher charging efficiency, this application requires an input voltage V... in Less than the above voltage threshold V th In this case, the first mode is preferred, that is, the current mode is switched to the first mode mentioned above to output the target power supply voltage.

[0070] S606, the power supply circuit of the display device supplies power to the OLED screen in the display device based on the target power supply voltage through a buck-boost converter.

[0071] It should be understood that OLED screens require multiple different supply voltages to operate properly. Among these different supply voltages is the target supply voltage V output by this application. out That is, a constant positive voltage ELVDD with a value of 4.6V.

[0072] Optionally, following S602, if it is determined that the input voltage changes from less than the voltage threshold to greater than the voltage threshold, the power supply circuit of the display device can also execute S607 through the buck-boost converter, that is, switch the current mode from the first mode to the second mode to output the target power supply voltage.

[0073] It should be understood that the first mode described above can only be used to maintain the target output supply voltage when the input voltage is less than the voltage threshold; the second mode described above is used to maintain the target output supply voltage when the input voltage is greater than or less than the voltage threshold. That is, when it is determined that the input voltage crosses the voltage threshold from low to high, i.e., the input voltage V... inA voltage threshold greater than the above value is 4.5V. th In order to maintain the target output supply voltage V out This allows you to switch the current mode from the first mode to the second mode mentioned above.

[0074] It should also be understood that, prior to S607 mentioned above, i.e., before switching from the current mode to the second mode, in order to ensure that the input voltage V... in Less than the voltage threshold V th The target supply voltage V can be maintained at the same time. out To achieve efficient power supply to the OLED screen in the display device, the current mode can be the first mode.

[0075] Optionally, following S604 above, if the time interval is less than or equal to the time threshold, the power supply circuit of the display device can also maintain the current mode as the second mode through the buck-boost converter to output the target power supply voltage.

[0076] It should be understood that the more frequently the mode is switched, the higher the frequency of output voltage fluctuations, and consequently the higher the probability of water ripples appearing, making them easier for users to notice. Therefore, this application can maintain the current mode unchanged when the interval is less than or equal to the time threshold, thereby reducing the frequency of mode switching and decreasing the probability of water ripples appearing as the frequency of output voltage fluctuations decreases.

[0077] Optionally, following S604 above, if the time interval is less than or equal to the time threshold, the power supply circuit of the display device can also execute S608 and S609 via the buck-boost converter.

[0078] S608, the power supply circuit of the display device obtains a new duration through a buck-boost converter, and determines whether the input voltage is lower than the voltage threshold when the sum of the interval duration and the new duration is greater than or equal to the aforementioned duration threshold.

[0079] S609, when it is determined that the above-mentioned input voltage is lower than the voltage threshold, the power supply circuit of the display device switches the current mode from the second mode to the first mode through the buck-boost converter.

[0080] It should be understood that, in order to avoid frequent mode switching leading to high voltage fluctuations and thus increasing the probability of water ripples, this application can perform a mode switching operation when the sum of the aforementioned time interval and the new time interval is greater than or equal to the aforementioned time interval threshold, thereby reducing the mode switching frequency and the probability of water ripples.

[0081] It should be understood that this application can also perform the above-mentioned mode switching operation according to the current charging state, so as to maintain the output target power supply voltage under the input voltage corresponding to different charging states, so as to realize the power supply method of the display device provided by this application.

[0082] Figure 7 This is a schematic diagram of a power supply method 700 for a display device provided in this application. This method 700 can also be applied to the power supply circuit of a display device in a charging architecture. Figure 7 As shown, the method 700 includes the following steps:

[0083] S701, the power supply circuit of the display device obtains input voltage from the power supply battery through a buck-boost converter.

[0084] S702, the power supply circuit of the display device determines the relationship between the input voltage and the voltage threshold through a buck-boost converter.

[0085] For example, this voltage threshold can also be called the switching point voltage, and can be expressed as V. th The value can be 4.5V. The above input voltage can be expressed as V. in The power supply circuit of the display device can compare the above input voltage with the voltage threshold through a buck-boost converter to determine their magnitude relationship.

[0086] S703, when it is determined that the input voltage changes from greater than the voltage threshold to less than the voltage threshold, the power supply circuit of the display device obtains the actual charging time through the buck-boost converter.

[0087] It should be understood that the first mode described above can only be used to maintain the target output supply voltage when the input voltage is less than the voltage threshold; the second mode described above is used to maintain the target output supply voltage when the input voltage is greater than or less than the voltage threshold. When determining the input voltage V... in From a voltage threshold greater than the above-mentioned V th The change is less than the aforementioned voltage threshold V. th In this case, before obtaining the actual charging time, it can be determined that before S703 mentioned above, in order to ensure that the input voltage V... in Greater than the voltage threshold V th The target supply voltage V can be maintained at the same time. out To enable power supply to the OLED screen in the display device, the current mode can be a second mode.

[0088] S704, the power supply circuit of the display device determines whether it is currently in a preset charging state based on the above charging time through a buck-boost converter.

[0089] It should be understood that the charging process may include multiple different charging stages or charging states. For example, the preset charging state mentioned above may be the slow charging state of the power supply battery or the charging state within a preset time period away from the slow charging state.

[0090] S705, when the current charging state is not a preset charging state, the power supply circuit of the display device switches the current mode from the second mode to the first mode through a buck-boost converter to output the target power supply voltage.

[0091] For example, corresponding to S704 above, if the preset charging state can be the slow charging state of the power supply battery or the charging state within a preset time period away from the slow charging state, then the non-preset charging state can be a non-slow charging state or a charging state within a non-preset time period away from the slow charging state.

[0092] It should be understood that when the aforementioned current charging state is not a preset charging state, the input voltage V in Typically, this can be maintained at a voltage threshold of less than 4.5V. th In order to achieve high-efficiency power supply, the current mode can be switched from the second mode to the first mode to output the target power supply voltage.

[0093] S706, the power supply circuit of the display device supplies power to the OLED screen in the display device based on the target supply voltage through a buck-boost converter.

[0094] Similarly, OLED screens require multiple different supply voltages to operate properly. Among these different supply voltages is the target supply voltage V output by this application. out That is, a constant positive voltage ELVDD with a value of 4.6V.

[0095] Optionally, following the above-mentioned S704, if the current charging state is the preset charging state, the power supply circuit of the display device can also execute S707 through the buck-boost converter, that is, maintain the above-mentioned current mode as the second mode to output the target power supply voltage.

[0096] It should be understood that during slow charging, the aforementioned input voltage V will be affected by the superimposed battery load fluctuations. in Voltage threshold V exceeding 4.5V th Therefore, given that the current charging state is the aforementioned preset charging state, in order to avoid frequent mode switching, the application can maintain the current mode as the second mode and output target power to achieve power supply to the OLED screen of the aforementioned display device.

[0097] For example, if the current charging state is within a preset time period from the slow charging state included in the aforementioned preset charging states, in this case, although the current determined input voltage V in Less than the voltage threshold V th However, in the upcoming slow charging state, the input voltage V in It will exceed 4.5V, and the first mode is only used at the above input voltage V. in Less than the above voltage threshold V th Under these circumstances, the target supply voltage is maintained. In other words, if the charging state is not considered, it will be necessary to switch from the second mode to the first mode and then from the first mode to the second mode in a short period of time, resulting in frequent mode switching and increasing the probability of water ripples appearing.

[0098] It should be understood that this application may also combine the charging status with the time interval between the last time the current mode was switched from the first mode to the second mode and then back to the first mode, and perform the above mode switching operation to further reduce the mode switching frequency.

[0099] In one possible scenario, when it is determined that the time interval is greater than the time threshold, the power supply circuit of the display device can also determine the current charging state through the buck-boost converter, and if the current charging state is the non-preset charging state, it can switch from the second mode to the first mode.

[0100] For example, when it is determined that the time interval is greater than the time threshold and the current charging state is a non-preset charging state, the power supply circuit of the display device can switch from the second mode to the first mode via a buck-boost converter. This avoids the input voltage V from being in the preset charging state, such as when about to enter a slow charging state. in For a short period of time, the voltage exceeds 4.5V, and the first mode is only used at the aforementioned input voltage V. in Less than the above voltage threshold V th In this case, maintaining the target power supply voltage for output requires switching the current mode from the second mode to the first mode and then back to the second mode in a short period of time, resulting in frequent mode switching and increasing the probability of water ripples appearing.

[0101] In another possible scenario, if the current charging state is the preset charging state, the power supply circuit of the display device can also maintain the second mode switching through the buck-boost converter to further reduce the frequency of mode switching and reduce the probability of water ripples appearing.

[0102] It should be understood that the power supply circuits for the aforementioned battery, OLED screen, and display device provided in this application can be located in different devices.

[0103] For example, the power supply circuit of the aforementioned power supply battery and the display device can be disposed in the power supply device, and the OLED screen is disposed in the aforementioned display device.

[0104] Optionally, the power supply circuit of the aforementioned power supply battery, OLED screen and the display device provided in this application may also be set in the same device, such as the display device, to realize the power supply method of the display device provided in this application. This application does not limit this.

[0105] Figure 8 This is a schematic diagram of the display device 800 provided in this application. Figure 8 As shown, the display device 800 includes a power supply battery 801, a power supply circuit 802, and an OLED screen. The power supply circuit may include a buck-boost converter 8021, which may be composed of a first MOSFET 80211 (Q1 80211), a second MOSFET 80212 (Q2 802112), a third MOSFET 80213 (Q3 80213), a fourth MOSFET 80214 (Q41 80214), and an inductor 80215 (L 80215). Figure 8 As shown, the first MOSFET 80211 can be connected in series with the second MOSFET 80212 to form a first series branch, and the third MOSFET 80213 and the fourth MOSFET 80214 can be connected in series to form a second series branch. The second series branch is connected in parallel with the first series branch and is connected through the inductor 80215.

[0106] It should be understood that Figure 8 The display device 800 shown is merely exemplary and is not intended to limit the scope of this application.

[0107] It should also be understood that the various embodiments described above can be coupled to each other, and this application does not limit this. Furthermore, the sequence number of each process does not imply the order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0108] The above description, in conjunction with specific implementation methods, provides a further detailed explanation of the embodiments of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A power supply circuit for a display device, characterized in that, This is applied to a power supply architecture, which further includes a power supply battery and a display device, the display device including an OLED screen. The power supply circuit includes a buck-boost converter, the power supply battery is connected to the power supply circuit, and the power supply circuit is connected to the display device, wherein: The power supply battery is used to transmit input voltage to the buck-boost converter; The buck-boost converter is used to switch the current mode to a first mode or a second mode according to the relationship between the input voltage and the voltage threshold and the current charging state, so as to output a target power supply voltage; and to supply power to the OLED screen in the display device through the target power supply voltage. Wherein, the switching time after switching the current mode from the first mode to the second mode and then switching the current mode back to the first mode is longer than a time threshold, the time threshold being determined based on the refresh rate of the display device; Specifically, when the input voltage changes from being greater than the voltage threshold to being less than the voltage threshold, the actual charging time is obtained; The current charging status is determined based on the actual charging time. If the current charging state is not a preset charging state, the current mode is switched from the second mode to the first mode. The non-preset charging state is a non-slow charging state or a charging state that is not within a preset time period from the slow charging state.

2. The power supply circuit according to claim 1, characterized in that, The first mode is used only to maintain the output of the target supply voltage when the input voltage is less than the voltage threshold; the second mode is used to maintain the output of the target supply voltage when the input voltage is greater than or less than the voltage threshold.

3. The power supply circuit according to claim 1, characterized in that, The buck-boost converter is used for: If it is determined that the input voltage changes from less than the voltage threshold to greater than the voltage threshold, the current mode is switched from the first mode to the second mode.

4. The power supply circuit according to claim 3, characterized in that, The buck-boost converter is used for: Get the time interval between the last time the current mode was switched from the first mode to the second mode and then back to the first mode; Determine the relationship between the interval duration and the duration threshold; If the time interval is greater than the time threshold, the current mode is switched from the second mode to the first mode.

5. The power supply circuit according to claim 4, characterized in that, The buck-boost converter is used for: If the time interval is less than or equal to the time threshold, the current mode remains the second mode.

6. The power supply circuit according to claim 5, characterized in that, The buck-boost converter is used for: The timer gains a new duration; If the sum of the interval duration and the new duration is greater than or equal to the duration threshold, determine whether the input voltage is lower than the voltage threshold. If it is determined that the input voltage is lower than the voltage threshold, the current mode is switched from the second mode to the first mode.

7. The power supply circuit according to claim 1, characterized in that, The buck-boost converter is used for: If the current charging state is a preset charging state, the current mode is maintained as the second mode; The preset charging state is either a slow charging state or a charging state within a preset time period away from the slow charging state.

8. The power supply circuit according to any one of claims 1 to 7, characterized in that, The buck-boost converter is composed of a first MOSFET, a second MOSFET, a third MOSFET, a fourth MOSFET, and an inductor. The first MOSFET and the second MOSFET are connected in series to form a first series branch, and the third MOSFET and the fourth MOSFET are connected in series to form a second series branch. The first series branch and the second series branch are connected in parallel and connected through the inductor. In the first mode, the first MOSFET is always on, while the third and fourth MOSFETs are alternately on; in the second mode, the first and second MOSFETs are alternately on, while the third and fourth MOSFETs are alternately on.

9. A power supply method for a display device, characterized in that, A power supply circuit for a display device applied in a power supply architecture, the power supply architecture further including a power supply battery and a display device, the display device including an OLED screen, the method comprising: The input voltage is obtained from the power supply battery; Based on the relationship between the input voltage and the voltage threshold, and the current charging state, the current mode is switched to the first mode or the second mode to output the target power supply voltage; The target power supply voltage is used to power the OLED screen in the display device; Wherein, the switching time after switching the current mode from the first mode to the second mode and then switching the current mode back to the first mode is longer than a time threshold, the time threshold being determined based on the refresh rate of the display device; The step of switching the current mode to the first mode or the second mode based on the relationship between the input voltage and the voltage threshold includes: When the input voltage changes from being greater than the voltage threshold to being less than the voltage threshold, the actual charging time is obtained; The current charging status is determined based on the actual charging time. If the current charging state is not a preset charging state, the current mode is switched from the second mode to the first mode. The non-preset charging state is a non-slow charging state or a charging state that is not within a preset time period from the slow charging state.

10. The method according to claim 9, characterized in that, The first mode is used only to maintain the output of the target supply voltage when the input voltage is less than the voltage threshold; the second mode is used to maintain the output of the target supply voltage when the input voltage is greater than or less than the voltage threshold.

11. The method according to claim 9, characterized in that, The step of switching the current mode to the first mode or the second mode based on the relationship between the input voltage and the voltage threshold includes: If it is determined that the input voltage changes from less than the voltage threshold to greater than the voltage threshold, the current mode is switched from the first mode to the second mode.

12. The method according to claim 11, characterized in that, Before switching the current mode from the second mode to the first mode, the method further includes: Get the time interval between the last time the current mode was switched from the first mode to the second mode and then back to the first mode; Determine the relationship between the interval duration and the duration threshold; Switching the current mode from the second mode to the first mode includes: If the time interval is greater than the time threshold, the current mode is switched from the second mode to the first mode.

13. The method according to claim 12, characterized in that, The method further includes: If the time interval is less than or equal to the time threshold, the current mode remains the second mode.

14. The method according to claim 13, characterized in that, The method further includes: The timer gains a new duration; If the sum of the interval duration and the new duration is greater than or equal to the duration threshold, determine whether the input voltage is less than the voltage threshold. If it is determined that the input voltage is less than the voltage threshold, the current mode is changed from the second mode to the first mode.

15. The method according to claim 9, characterized in that, The method further includes: If the current charging state is a preset charging state, the current mode is maintained as the second mode; The preset charging state is either a slow charging state or a charging state within a preset time period away from the slow charging state.

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